1. Field of the Invention
This invention relates to packing in boxes, for shipping, of empty collapsible tubes by the tube manufacturer to the product manufacturer who fills and seals the tubes.
2. Background Art
Collapsible tubes are used to contain and dispense fluids wherein the wall of the tube is deformed to squeeze out the fluid. Such tubes are made by a tube manufacturer and then shipped, empty, with the bottom open and up for filling and sealing by the product manufacturer. The tubes are shipped with the closure caps attached. The wall material is in some instances of tin, and in other instances of aluminum or even laminates. Such material is easily deformed so that the empty tubes must be carefully packed for, and protected during, shipment. Also, particularly in the case of pharmaceuticals, the tube must be kept perfectly clean in packing, shipping, and unpacking for filling, to prevent contaminating the contents.
Thus, the packing and shipping of empty collapsible tubes is of utmost importance to a tube manufacturer and much effort and expense is devoted to this phase of a tube manufacturer's operations.
The tubes are shipped in either partitioned boxes or partitionless boxes.
The tubes are in most instances in one of ten standard size outside diameters (O.D.'s) that range from 1/2" to 11/2" in 1/2" increments. There are specialty orders for other sizes, but the standard sizes constitute the vast bulk of the business.
When shipped in partitioned boxes, separate small compartments formed by internesting dividers give a separate space for each tube, with accompanying protection.
In a partitionless box, the tubes are in contact with one another and are arranged vertically in the box, side by side. The tubes abut one another in such side by side relationship to form a honeycomb effect which gives a strong measure of strength and protection against damage to the tubes. It is critical that the tubes be not too tightly pressed against one another to avoid, among other things, damage in packing, since they are either hand-packed or machine-packed by placement of tubes so that they extend vertically in the box, one against another, when the box extends horizontally. Hence, the box must of a proper size for the number of tubes packed.
Most of the shipping is done in partitionless boxes, thus eliminating the cost of the partitions and permitting more tubes to be shipped per box. The tubes are packed in a partitionless box by hand or by machine. In packing a partitionless box by hand, the tubes are either inserted into the box vertically, the box extending horizontally, or, in the alternative, the box is at an incline, for instance 45.degree., and the tubes are laid at an angle to obtain the benefit of both side nesting and bottom nesting into the box.
In one form of machine packing of a partitionless box, the box extends vertically and a given number of tubes in a horizontal row, for instance 31, which would occupy the length of the box, are simultaneously placed into the box horizontally by a movable tray which abuts the top of the tubes. The machine is programmed to lower the box to receive successive, horizontal rows of tubes. After the box is fully packed, it is rotated into a horizontal position wherein the tubes extend vertically, inverted, with the open bottoms extending across the top of the box.
In either form of packing, the end desired result is a compact arrangement of vertically extending tubes resting with the heads and caps thereon at the bottom of the box and open bottoms of the tubes extending across the top of the box. The vertical dimension of the box depends on the height of the tube. For instance, in a tube having a 21/2" overall length including the cap, the vertical dimensions of the box would be such as to permit the tubes to be contained vertically within the box and cover.
In a procedure used in Europe, the open ends of the tubes extend above the top of the box, creating a columned effect. The cover rests right on top of the tubes.
In the United States, the more general policy is to use a box that extends above the tubes, for instance 1/8", so there is some vertical play which is not harmful since the tubes are relatively restrained sideways, so that virtually no jumbling occurs. A problem with "play" vertically of the tubes is that they have a tendency to move longitudinally, one with respect to another, or rotate axially, one with respect to another, so that some rubbing or marring of the tube surface and decoration occurs.
To hold the packed tubes properly, boxes of the prior art for packing and shipping tubes came in many horizontal dimensions; that is, length and width. These were determined by the following:
1) In some instances, the box dimension was based on a customer's request for a box to contain a certain number of tubes. For instance, a customer might want a box for a gross (144) and the box would be designed to hold, for instance, 12 rows, 12 across. The outside dimension (O.D.) of the tube would be taken into consideration, and a box simply designed for that number of tubes, taking into consideration the necessary spacing needed for the procedure of packing as discussed above, and the necessary closeness to provide proper protection for the tubes, as again discussed above. The box dimension, hence, was calculated from both the tube size and, from past experience, the necessary clearance and the necessary tightness.
Again, where a partition was used as was often the case with a 12.times.12 gross box, the thickness of the partition was calculated into the box dimensions.
2) In other instances, the box dimension was based on a number of tubes which was, in effect, arbitrary. For instance, a customer would determine that a certain size box would fit, for example, a cassette in its filling machine and, hence, order a number of tubes and that size box, based on this consideration.
3) In still another instance, the skid on which the filled boxes are packed and secured, as by shrink wrapping, determined the desired size box and the amount per trailer of these boxes.
4) Still another consideration might be the size of the sterilization chamber when such is used. (Sometimes the customer sterilizes the tubes before filling.) In that instance, a box size is selected which is compatible with the sterilization chamber, and then the tubes are packed accordingly.
It will be seen from the above examples that the box size is determined in such a way that there is virtually an infinite number of sizes which must be provided. Bearing in mind that the above examples must also compensate for the ten various size standard outside diameters (O.D.'s), it will be seen that, for instance, where a box is determined by a gross (144) number, there would have to be ten different size boxes for the ten relatively standard size tubes, referring to the horizontal dimension of the boxes. Where a box size is determined by the pallet capacity and the trailer capacity, again there must be virtually a specific box size for every different size of tube.
As shown in the above examples, the result is that tube manufacturers must have an enormous number of box sizes as a possibility and, practically, there has evolved this necessity for an inventory of a great number of box sizes which must be provided by the tube manufacturer. The provision and use of such an inventory is expensive.